Climate control unit with germ-proof separated sections

ABSTRACT

Climate control unit with an interior section containing a storage space and with a closable access opening to the storage section whereby at least one part of the interior section is separated and sealed against the rest of the interior section thus forming a separate germ-proof section. The division takes place at least in part by a membrane that is permeable for water vapor and gas but impermeable for microorganisms.

This application is a continuation of co-pending U.S. application Ser.No. 11/029,630, filed Jan. 6, 2005, the disclosure of which is herebyexpressly incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The invention concerns a climate control unit with an internal sectioncontaining a storage section and with a closable access opening to thestorage section and also a membrane box for application in such aclimate control unit.

BACKGROUND OF THE INVENTION

A climate control unit is a laboratory apparatus for the storage ofpredominantly biological or chemical specimens in definite climaticconditions. Examples of this are incubators and cooling or freezingunits. Such climate control units have a storage section that isenclosed by a housing making it gastight and thermally isolated. Thestorage section is accessible via an opening that frequently takes upthe entire front side of the climate control unit and that can be closedwith a closing device so that it is gastight. Usually the storagesection is provided with horizontal inserts for storing the specimens.Climate control units of such type offer in their storage section aclimate with predetermined temperature and air moisture and also apredetermined CO.sub.2 concentration in the case of incubators. Theclosing device is often an external swing door behind which usually atransparent inner door is arranged as a gas screen. This transparentinner door prevents a fast gas exchange from taking place between thestorage section and the surroundings when the external swing door isopened. At the same time the transparent gas screen allows the view ofthe samples. So opening times of the gas screen can be reduced to aminimum, thus largely avoiding unnecessary disturbances in the storagesection climate. In order to further reduce disturbances, dividedenclosures and partitioned gas screens are known. For example, there aregas screens with six separate access openings each of which is closableby its own door. Such partitioned gas screens make it possible to accessdefinite enclosures and storage cells whereby the other storage cellsstay protected.

A prevalent method for the humidification of the atmosphere of anincubator takes place via passive evaporation of water in an open waterbath (water bath). While the advantage is a very homogenous distributionof moisture in the air, the disadvantage is the open water surface. Dirtparticles, viruses, fungi, bacteria and mycoplasma grow in the waterbath in great quantity once they have entered into the water throughdrops or dust.

A risk of contamination exists for the specimens also through otherspecimens. On the one hand the specimens can be infested with foreigngerms such as fungi or bacteria. On the other hand even the specimensthemselves can be dangerous agents. This can mean a risk for otherspecimens through cross-contamination and also for the operating person.If the storage section of the climate control unit is contaminated,mostly an expensive disinfection of the entire equipment is requiredresulting in long down times.

For the prevention of contamination and cross-contamination membranepouches made out of germ-proof membrane are known. Individual specimencarriers can be packed and sealed in such membrane pouches and stored ina climate control unit. However the handling of these membrane pouchesis considered to be inconvenient. Accordingly they find a low level ofacceptance among users.

With this background the task underlying the present invention is tospecify a climate control unit that reduces the risk of contamination ofthe entire equipment and of cross-contamination and is user-friendly inspite of that.

SUMMARY OF THE INVENTION

A climate control unit in accordance with one embodiment thus has aninterior section containing a storage section and a closable accessopening to the storage section whereby at least one part of the interiorsection is separated from the rest of the interior section, making itgerm-proof. Thus germ-proof separated section is formed. The separationis made possible at least partly by a membrane that is permeable forwater vapor and gas but impermeable for microorganisms.

The advantage as opposed to the prior art lies in the fact that an acutecontamination in one part of the interior section cannot encroach uponthe other parts of the interior section. A cross-contamination betweendifferent germ-proof separate parts is not possible. Therefore in caseof a contamination, the whole interior section does not need to bedisinfected, instead only a sub area.

The germ-proof separation takes place at least partly via a membranethat is permeable for water vapor and gas, but impermeable formicroorganisms. The permeability of the membrane is determined by itspores. The pores must be sufficiently big so that water vapor and gascan penetrate the membrane unobstructed as far as possible. On the otherhand the size of the pores should be restrictive in such a manner thateven the smallest microorganisms cannot penetrate the pores.Preferentially the membrane therefore has pores whose maximum size is0.5 .mu.m. and a particularly preferable pore size that is smaller than0.2 .mu.m.

The climate control unit can be an equipment that controls only thetemperature of the interior section like a cooling or freezing unit.Preferentially the climate control unit is an equipment thatadditionally allows the adjustment of the atmosphere in the storagesection like an incubator.

In an advantageous design variant the climate control unit has a gasscreen between the access opening and the interior of the climatecontrol unit. The gas screen closes the interior section of the climatecontrol unit. The use of the gas screen both as a swing door and also agas screen that can be pulled out on rails can be advantageous. Apartitioned gas screen with several openings is particularlypreferential. Several openings allow access to individual compartmentsin the climate control unit with minimum disturbance to the atmospherein the remaining compartments.

Through germ-proof separation of individual sections in the interiorsection of the climate control unit by means of a membrane, disturbancesof the atmosphere are further reduced. The membrane is preferentiallystretched over a frame and mounted on it. In another variant of theinvention the frame is attached inside the climate control unit andequipped with a sealing mechanism so that it is sealed off from one orseveral interior walls of the climate control unit. In this manner e.g.,a tray on the floor or a dent in an interior wall of the climate controlunit is covered with a membrane and separated from the remaininginterior section, making it germ-proof. Depending on the purpose ofapplication, the frame can be set in the force fit with a flexiblesealing in the inner housing of the climate control unit or it can bemounted permanently. Also a sealing with other current methods e.g.,with silicon sealing and gravitational force or compression by boltforce is possible.

In an advantageous design form of the climate control unit, electriccomponents such as motors or ventilators and sensors are accommodated insuch a germ-proof and separated section for protection againstcontamination. It is particularly advantageous if a water bath providedfor the humidification of the storage section is protected in thismanner by a membrane. Since the membrane is permeable for gas and watervapor moisture can diffuse into the entire storage section. This isparticularly supported if the water bath is tempered and if additionallya ventilator is provided in the separated section that promotes thediffusion of the moist air. It is also possible to rinse the moist airby means of a ventilator through a membrane tube that is led through thestorage section and thus provides for even moisture in the storagesection.

Fumigation of the specimens can increase the moisture in the storagesection. Therefore in a preferential design form of the climate controlunit a heat bridge (cold spot) is attached between the separated sectionwith the water bath and the storage section. Excess moisture in thestorage section condenses on it and can be led back into the waterreservoir.

In another preferential design form a part of the storage section isseparated by a membrane box thus making it germ-proof. The membrane boxis enclosed by walls making it germ-proof, whereby at least one part ofthe wall surfaces consists of membrane. The membrane should be measuredsuch that a sufficient exchange of gas and moisture can take place. Ingeneral it is sufficient if e.g., only one sidewall is made out ofmembrane and the rest of the walls out of gastight material. A membranebox offers space for one or several specimen containers. The climatecontrol unit can in turn have either one or several membrane boxes. Inthe extreme case one membrane box takes up the entire storage section ofthe climate control unit. In case of several membrane boxes, it isessential that they do not cover the membranes in a two-way manner sothat the diffusion of gas and moisture is not obstructed. Therefore itis meaningful not to fill out the entire storage section of the climatecontrol unit with membrane boxes instead to let intermediate sectionsfree so that the diffusion can take place without obstruction. In orderto further improve the diffusion, the air exchange in the storagesection can be increased e.g., by arrangement of ventilators.

It is particularly preferential to divide the entire storage section ofthe climate control unit by membrane boxes. A cross-contaminationbetween the individual boxes is not possible. In case of contaminationin one membrane box, the concerned box can be replaced and disinfectedindividually or destroyed. A further advantage lies in the fact that theair moisture in the climate control unit in accordance with theinvention can be increased as opposed to devices of prior art. The riskof contamination through condensed water is strongly reduced by themembrane partitions. A higher moisture level offers better protectionfrom the withering of the specimens. The individual membrane boxes canbe mounted permanently in the climate control unit. It is preferable toreleasably attach them in the interior section of the climate controlunit with a fixing device. In the interior section of the climatecontrol unit e.g., a base frame or a frame can be provided in whichseveral membrane boxes are inserted. Also a pullout mechanism of thetype of drawers is possible. Hanging the membrane boxes in the innerspace can be particularly advantageous, besides also saving material. Itis also useful if the membrane box is fastened to one or severalinterior walls of the climate control unit.

In a variant of the design form of the invention the membrane box isreleasably fastened to the gas screen of the climate control unit. Thusit can be inserted from the front into an opening of the closed gasscreen and can be fastened with a quick-release fastener. In anothervariant the membrane box is permanently mounted on the reverse side ofthe gas screen. Then the membrane box can be folded or pulled from theinterior section of the climate control unit when the gas screen isopened. In this case the membrane box is sealed against the gas screenon the front side via a sealing. The gas screen then forms the frontwall of the membrane box.

It is advantageous that the membrane box has at least one opening forthe loading and unloading of specimens. The opening is releasablyclosable with a closing device that thus makes it germ-proof.Preferentially this closing device consists of a door. Other variantsare membrane parts that are put on top of each other or also a screwclosure. It is meaningful if the membrane box has such an opening forloading at the front side and at the reverse side. The membrane box canthen be inserted into the climate control unit with any of the sides atthe front.

When the membrane box is sealed at the front side from the gas screen itis particularly advantageous if a closing device is integrated into thegas screen. Thereby the membrane box can either be fastened in theinterior section of the climate control unit, e.g., on a frame or a baseframe, and can be sealed against the gas screen at its open front sidevia a flexible sealing. Spring systems are useful for increasing thesurface pressure. The inner space of the membrane box is accessible viaa door integrated into the gas screen in this design form. In its crosssection, the door is then purposefully smaller than the cross section ofthe membrane box, with which this is sealed to the gas screen. Theadvantage of such a design form lies in its easy usability. Eachmembrane box is directly accessible via a door in the gas screen.

In another preferential variant the closing device is directly fastenedto the membrane box. This makes it possible for the whole membrane boxto be pulled out of the climate control unit in its germ-proof andclosed state. Thus specimens can be transported in germ-proofsurroundings from one equipment to other equipments e.g., in vacuumcupboards, drying cupboards or microbiological safety cabinets. Such amembrane box is purposefully pushed from the front into a gas screen. Agas screen must have openings for it that are adjusted to thecross-section of the membrane boxes. If a membrane box was pulled out ofthe gas screen the resulting aperture can be covered with a substituteclosing device. This is also possible by an automatic mechanism.

The task of the invention is also solved by a membrane box forapplication in a climate control unit whereby the membrane box isenclosed by walls making it germ-proof and at least one sub area ofthese walls is formed by a membrane. The membrane is permeable for gasand water vapor but impermeable for microorganisms. The membrane box hasat least one load opening that can be releasably closed to make itgerm-proof via a closing device, particularly a door. As described abovethe closing device can also consist of membrane parts or a screwclosure. It is useful if the load opening is aligned with the accessopening of the climate control unit. The closing device can also beconnected functionally to the access opening of the climate controlunit.

It is mostly sufficient if the membrane box has only one membrane windowand otherwise has a gastight formation. For the gastight closure of themembrane box it is then sufficient if the membrane window is coveredthus making it gastight. The membrane box can also have a closable form.

Preferentially the membrane has pores with a maximum size of 0.5 .mu.m.A pore size smaller than 0.2 .mu.m is particularly advantageous.

In a preferential design form, the membrane box has at least one viewwindow. A view window is meaningful at the front side particularly ifthe membrane box is integrated with its front side into the gas screen.Additionally a view window can be meaningful in the topside so that onecan observe the specimens well if the membrane box is taken out of theclimate control unit. A view window is meaningful on the lower side ifthe specimens are supposed to be analyzed with a reverse microscopewithout being taken out of the germ-proof atmosphere. A membrane boxtaken out of the climate control unit is purposefully self-supportingand stackable with other membrane boxes of similar type. It isadvantageous if the membrane box is adjusted in its shape to thespecimen containers to be used. Usually it is cuboid. On the contrary,for the germ-proof storage of bottles cylindrical membrane boxes can bemore meaningful. A cylindrical membrane box can also be provided with ascrew closure instead of a door. Also an adjustment of the membraneboxes to the shape of the climate control unit is also convenient sothat the membrane boxes can be put in and taken out of the climatecontrol unit with accuracy in fitting.

In another variant of the design form the membrane box has a closingdevice that closes automatically when the membrane box is taken out ofthe climate control unit. This can be e.g., a flap (shutter) that opensand automatically falls back when something is inserted into or takenout of the climate control unit respectively. For the transport ofunfilled membrane boxes it is advantageous if these can be foldedtogether flatly similar to a paper bag or an accordion.

A membrane box is purposefully manufactured out of sterile material.This can be in case of steam sterilization e.g., heat-resistant plastic.Also chemical methods for disinfection are possible after acontamination. In the case of a contamination with dangerous agents,sterilization in an equipment is also thinkable whereby the membrane boxis destroyed. During their delivery in the sale process, unused membraneboxes are themselves sterile. They are packed sterilely and folded in aspace-saving manner.

For the transport of a filled membrane box it has advantageously atransport container in which the membrane box can be enclosed making itwater vapor-tight and gas-tight. Such a transport container haspreferentially at least one view window or is at least manufactured inpart or completely out of transparent material.

In an advantageous design form the transport container has a device fortempering for longer transports. This can take place throughbattery-backed systems or simply through a heat saving material withhigh heat capacity. A simpler variant maintains the temperature alonethrough thermal isolation.

Also a device for the reception and control of the gas composition inthe transport container is purposeful. This happens e.g., by means of aconnected transportable gas bottle.

For the reception of the air moisture in the transport container, thelatter has a moisture device. This can be a water reservoir in thetransport container. In order to avoid the flowing of water in thetransport container preferentially a sponge structure soaked with wateris used as moisture device. For heating, gas supply and activehumidification battery-operated systems are possible that can becontrolled via independent control circuits.

Additionally the transport container can have a closable formation.

In a preferential design form the membrane box or the transportcontainer has a reader for transmitting information about specimens. Thereader can communicate with an evaluation unit. The information aboutspecimens can be saved on a bar code or magnetic strips. Whilepositioning the specimens into the membrane box or in the transportcontainer this information is recorded by a reader automatically. Thereader in turn can communicate with an evaluation unit. For purposes ofchecking and data recording it is connected e.g., to a PC. Thiscommunication can also occur wirelessly e.g., with Bluetooth technology.

For carrying a membrane box from a climate control unit into a transportcontainer with minimum disturbance of the atmosphere in the membrane boxthe transport container has an opening. This opening can be sealedagainst the gas screen of a climate control unit thus making itgastight. The transport container also has a closing instrument, whichessentially prevents the intrusion of the outside atmosphere into thetransport container. The transport container can be fastened to the gasscreen of the climate control unit such that the opening of thetransport container encloses the front side of the membrane box insertedin the gas screen. The membrane box is then put into the transportcontainer. During this transfer the membrane box can always remain incontrolled atmosphere. Similarly the reverse route of transport is alsopossible. Thereby the membrane box can be created such that the reversewall of the membrane box is itself gastight and forms the gastight rearwall of the transport container.

In another variant the membrane box is completely inserted in thetransport container and behind the membrane box the transport containeris closed with a sliding device before the transport container isreleased from the gas screen.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention is explained on the basis of examples ofimplementation illustrated in the figures.

The figures illustrate schematically:

FIG. 1: a side view of a climate control unit in vertical sectionthrough the front center with sections separated by membranes;

FIG. 2: a front view of the opened front side of a climate control unitwith foldable gas screen and membrane boxes that are open to the frontand separate doors that are integrated into the gas screen;

FIG. 3: a top view of a membrane box that is open to the front and issealed against the gas screen and whose door is attached to the gasscreen.

FIG. 4: a top view of another version of a membrane box with a doorattached to it that is inserted into the gas screen from the front.

FIG. 5: a side view of a section of a membrane box that can be taken outin accordance with FIG. 4, that can be inserted into a transportcontainer and whose gastight rear wall forms the rear wall of thetransport container and

FIG. 6: a side view of a section of another version of a membrane box inaccordance with FIG. 4 in a transport container that is closed behindthe membrane box by a sliding device.

DETAILED DESCRIPTION

FIG. 1 illustrates a climate control unit 10 with an interior section 11that is accessible by a closable access opening 13. The swinging door 31that closes the interior section 11 is illustrated in side view and inan opened state. In the interior section of the climate control unit areseveral sections 14 divided by membranes 15. The floor of the interiorsection is covered by a water bath 18. The water bath is sealed by amembrane 15 stretched on a frame and sealings 28 along the sidewalls ofthe interior section against the storage space 12. For better diffusionin the interior section ii, the section 14 with the water bath isadditionally equipped with a ventilator 19. In the rear wall of theinterior section is a recess that is sealed against the storage section12 by a membrane 15. Inside this separated section 14 is a sensor 17.Another sensor 17 is attached in a section 14 that is separated by amembrane 15. The sensor 17 is attached in the corner between the ceilingand rear wall of the interior section. For storing the specimens theinterior section is provided with shelf-like horizontal inserts 23. Aclosed membrane box 20 is located on an insert. The membrane box 20separates an additional part of the interior section by a membrane.

In FIG. 2 six such membrane boxes 20 are illustrated in the interiorsection 11 of a climate control unit. This design variant of membraneboxes 20 is open to the front and equipped with a sealing 28. Themembrane boxes are sealed to the front by a gas screen 16 that isillustrated here in an opened state. Every membrane box is accessible bya separate door 25 in the gas screen 16. The membrane boxes 20 do notfill out the entire interior section of the climate control unit 10 soas to enable the diffusion of moist air. The arrows in the illustrationillustrate the diffusion. However they do not in any way represent orrestrict the actual streaming in the climate control unit.

FIG. 3 illustrates the top view of a membrane box 20 as in FIG. 2. Themembrane box 20 closes at its opening 24 with a sealing 28 against thegas screen 16. The opening in the gas screen can be closed by a door 25attached to the gas screen.

Another version of a membrane box is illustrated in FIG. 4. Thismembrane box 20 has a door 25 that is itself attached to the membranebox. According to this variant of the design form, the membrane box 20can be completely taken out of the climate control unit 11 in its closedstate. Built in the climate control unit 10 it is inserted from thefront into the opening of a gas screen 16.

FIG. 5 illustrates another variant of this design form. The membrane box20 is inserted halfway into the interior section ii of the climatecontrol unit and is inserted by a gas screen 16 into a transportcontainer 26. The transport container 26 has a carrying handle and isconnected to the gas screen 16 via seals 28. The membrane box 20 has agastight rear wall 29 that in the inserted state also forms the rearwall of the transport container 26.

FIG. 6 illustrates another variant of a membrane box 20 in a transportcontainer 26. In this illustration the membrane box is completelyinserted into the transport container. The transport container 26 isconnected via sealings against the gas screen 16 of the climate controlunit. The transport container 26 is closed with a sliding device 30while it is still connected to the gas screen 16 and the atmosphere ofthe climate control unit 10. The transport container 26 is released fromthe climate control unit only when it 26 is closed.

1.-34. (canceled)
 35. A climate control unit, comprising: a door; and ahousing defining a climate-controlled interior section, the interiorsection being accessible by an access opening that is closable by thedoor, the interior section including: a plurality of individualsections, and at least one membrane separating the interior section intoat least two of the individual sections, at least one of the twoindividual sections defining a germ-proof separated space, the membranebeing permeable for water vapor and gas and impermeable formicroorganisms.
 36. The climate control unit of claim 35, wherein themembrane has pores with a maximum pore size of 0.5 μm.
 37. The climatecontrol unit of claim 35, wherein the climate control unit is anincubator.
 38. The climate control unit of claim 35, further comprisinga gas screen that is arranged between the access opening and theinterior section of the climate control unit, whereby the gas screencloses the interior section of the climate control unit.
 39. The climatecontrol unit of claim 35, wherein the membrane is fastened on a framefixed to the interior section of the climate control unit.
 40. Theclimate control unit of claim 35, wherein the interior section containssensors and/or electric components of the climate control unit.
 41. Theclimate control unit of claim 35, wherein the interior section containsa water bath.